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Earthquake rocks Montana early Thursday

The 5.8-magnitude earthquake in western Montana took place just after midnight, local time. It woke people up near the epicenter and was felt throughout the region. Expect aftershocks.

Map via USGS

A 5.8-magnitude earthquake struck in western Montana early Thursday morning, waking people up more than 30 miles from its epicenter, and felt as far away as Spokane, Washington. The magnitude 5.8 quake occurred at 12:30 a.m. MDT (local time), about 6 miles (10 km) southeast of Lincoln, Montana, according to the U.S. Geological Survey (USGS). CBS Missoula affiliate KPAX-TV reported no immediate reports of injuries, but said 9-1-1 call centers were swamped with calls and was advising people to only call if they were injured. KMVT-TV in Twin Falls, Idaho reported power outages around the earthquake’s epicenter. USGS gave these details:

Geographic coordinates: 46.899N, 112.586W
Magnitude: 5.8
Depth: 4 km
Universal Time (UTC): 6 Jul 2017 06:30:16
Time near the Epicenter: 6 Jul 2017 00:30:16

Location with respect to nearby cities:
9.5 km (5.9 mi) SE of Lincoln, Montana
54.1 km (33.6 mi) NW of Helena, Montana
99.6 km (61.8 mi) N of Butte, Montana
107.3 km (66.5 mi) E of Missoula, Montana
111.0 km (68.8 mi) N of Butte-Silver Bow (Balance), Montana

Earthquakes do occur periodically in Montana, but this one was relatively strong – therefore relatively rare – for the region.

Did you feel it? Tell USGS

USGS also provided this background:

Western Montana and northwestern Wyoming have experienced at least 16 other M 5+ earthquakes within 300 km of the July 6, 2017 event over the preceding century. The largest was the August 1959 M 7.2 Hebgen Lake earthquake – the largest historic event in the intermountain region – which occurred about 280 km to the south-southeast of the July 6 event. The Hebgen Lake earthquake triggered a large landslide that resulted in significant damage and more than 28 fatalities. A M 6.9 earthquake just over 100 km to the southeast of the July 6th earthquake in June, 1925, caused significant damage, but no fatalities. A M 5.6 earthquake occurred 170 km to the south of the July 6th event in July 2005, and caused minor damage in the surrounding region.

Bottom line: The 5.8-magnitude earthquake in western Montana on Thursday, July 6, 2017, is expected to be followed by aftershocks.

Deborah Byrd

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